UBUNTU-CVE-2018-1095

Description

The ext4_xattr_check_entries function in fs/ext4/xattr.c in the Linux kernel through 4.15.15 does not properly validate xattr sizes, which causes misinterpretation of a size as an error code, and consequently allows attackers to cause a denial of service (get_acl NULL pointer dereference and system crash) via a crafted ext4 image.

CVSS Metrics

• v3.0•MEDIUM•Score: 5.5CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Affected Systems

• ubuntu•linux

  < 4.15.0-24.26

• ubuntu•linux-aws

  < 4.15.0-1011.11

• ubuntu•linux-azure

  < 4.15.0-1014.14~16.04.1 | < 4.15.0-1014.14

• ubuntu•linux-gcp

  < 4.15.0-1014.14~16.04.1 | < 4.15.0-1010.10

• ubuntu•linux-hwe

  < 4.15.0-24.26~16.04.1

• ubuntu•linux-kvm

  < 4.15.0-1012.12

• ubuntu•linux-oem

  < 4.15.0-1009.12

• ubuntu•linux-raspi2

  < 4.15.0-1013.14

References (5)

• https://ubuntu.com/security/CVE-2018-1095
• https://bugzilla.kernel.org/show_bug.cgi?id=199185
• https://ubuntu.com/security/notices/USN-3695-1
• https://ubuntu.com/security/notices/USN-3695-2
• https://www.cve.org/CVERecord?id=CVE-2018-1095